Computer graphics or image rendering is the process by which a computing system displays an image based on a computer program. A scene file containing information regarding objects in a scene is passed to one or more processing units that render an image for display based on the scene file. A display contains an array of pixels, each of which is the smallest addressable element in the display device. Rendering each pixel of a display to generate a high-resolution image is computationally intensive. To reduce the rendering workload, some regions of an image may be rendered at lower resolution by leaving “holes”, or unrendered pixels. The holes may be “filled in” with techniques of varying complexity in an attempt to make them less obvious. However, the result of leaving holes at regions of the image that are of interest to a viewer and the method to fill them in may noticeably detract from the image quality.